Production and decay of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>X</mml:mi><mml:mn>0</mml:mn></mml:msub><mml:mo stretchy="false">(</mml:mo><mml:mn>2900</mml:mn><mml:mo stretchy="false">)</mml:mo>

The observation of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msub><a:mi>X</a:mi><a:mn>0</a:mn></a:msub><a:mo stretchy="false">(</a:mo><a:mn>2900</a:mn><a:mo stretchy="false">)</a:mo></a:math> in the <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msup><e:mi>B</e:mi><e:mo>+</e:mo></e:msup><e:mo stretchy="false">→</e:mo><e:msup><e:mi>D</e:mi><e:mo>+</e:mo></e:msup><e:msup><e:mi>D</e:mi><e:mo>−</e:mo></e:msup><e:msup><e:mi>K</e:mi><e:mo>+</e:mo></e:msup></e:math> decay process indicates the existence of open flavor tetraquark states. We investigate the production and decay of the <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:msub><h:mi>X</h:mi><h:mn>0</h:mn></h:msub><h:mo stretchy="false">(</h:mo><h:mn>2900</h:mn><h:mo stretchy="false">)</h:mo></h:math> state with the final state interaction mechanism, where we calculate the strong vertices such as <l:math xmlns:l="http://www.w3.org/1998/Math/MathML" display="inline"><l:msub><l:mi>g</l:mi><l:mrow><l:mover accent="true"><l:mi>D</l:mi><l:mo stretchy="false">¯</l:mo></l:mover><l:mi>K</l:mi><l:msub><l:mi>X</l:mi><l:mn>0</l:mn></l:msub></l:mrow></l:msub></l:math>, <p:math xmlns:p="http://www.w3.org/1998/Math/MathML" display="inline"><p:msub><p:mi>g</p:mi><p:mrow><p:msup><p:mover accent="true"><p:mi>D</p:mi><p:mo stretchy="false">¯</p:mo></p:mover><p:mo>*</p:mo></p:msup><p:msup><p:mi>K</p:mi><p:mo>*</p:mo></p:msup><p:msub><p:mi>X</p:mi><p:mn>0</p:mn></p:msub></p:mrow></p:msub></p:math>, <t:math xmlns:t="http://www.w3.org/1998/Math/MathML" display="inline"><t:msub><t:mi>g</t:mi><t:mrow><t:msubsup><t:mi>D</t:mi><t:mi>s</t:mi><t:mo>*</t:mo></t:msubsup><t:mover accent="true"><t:mi>D</t:mi><t:mo stretchy="false">¯</t:mo></t:mover><t:mi>K</t:mi></t:mrow></t:msub></t:math>, and <x:math xmlns:x="http://www.w3.org/1998/Math/MathML" display="inline"><x:msub><x:mi>g</x:mi><x:mrow><x:msub><x:mi>D</x:mi><x:mrow><x:mi>s</x:mi><x:mn>1</x:mn></x:mrow></x:msub><x:mover accent="true"><x:mi>D</x:mi><x:mo stretchy="false">¯</x:mo></x:mover><x:msup><x:mi>K</x:mi><x:mo>*</x:mo></x:msup></x:mrow></x:msub></x:math> in the framework of the QCD sum rule method. We find that for the interpretation of the <bb:math xmlns:bb="http://www.w3.org/1998/Math/MathML" display="inline"><bb:msup><bb:mover accent="true"><bb:mi>D</bb:mi><bb:mo stretchy="false">¯</bb:mo></bb:mover><bb:mo>*</bb:mo></bb:msup><bb:msup><bb:mi>K</bb:mi><bb:mo>*</bb:mo></bb:msup></bb:math> molecule of <fb:math xmlns:fb="http://www.w3.org/1998/Math/MathML" display="inline"><fb:msub><fb:mi>X</fb:mi><fb:mn>0</fb:mn></fb:msub><fb:mo stretchy="false">(</fb:mo><fb:mn>2900</fb:mn><fb:mo stretchy="false">)</fb:mo></fb:math>, the branching fraction of the production process and the decay width are consistent with the experimental results, indicating that the observed <jb:math xmlns:jb="http://www.w3.org/1998/Math/MathML" display="inline"><jb:msub><jb:mi>X</jb:mi><jb:mn>0</jb:mn></jb:msub><jb:mo stretchy="false">(</jb:mo><jb:mn>2900</jb:mn><jb:mo stretchy="false">)</jb:mo></jb:math> could be interpreted as a <nb:math xmlns:nb="http://www.w3.org/1998/Math/MathML" display="inline"><nb:msup><nb:mover accent="true"><nb:mi>D</nb:mi><nb:mo stretchy="false">¯</nb:mo></nb:mover><nb:mo>*</nb:mo></nb:msup><nb:msup><nb:mi>K</nb:mi><nb:mo>*</nb:mo></nb:msup></nb:math> molecule. However, we cannot exclude the possibility of a compact tetraquark interpretation within the uncertainty. More experimental and theoretical efforts are needed to fully understand the nature of the <rb:math xmlns:rb="http://www.w3.org/1998/Math/MathML" display="inline"><rb:msub><rb:mi>X</rb:mi><rb:mn>0</rb:mn></rb:msub><rb:mo stretchy="false">(</rb:mo><rb:mn>2900</rb:mn><rb:mo stretchy="false">)</rb:mo></rb:math> state.