In the above reaction, left hand side and right hand side rings are named as ‘ A ’ and ‘ B ’ respectively. They undergo ring expansion. The correct statement for this process is:

Step-by-step solution

The reaction proceeds through a carbocation intermediate. The carbocation formed undergo rearrangement by ring expansion. Four membered ring undergo ring expansion to five membered ring and five membered ring undergo ring expansion to six membered ring and finally it converts to alkene by losing proton.