JEE Main Chemistry question

Compound 'A' (molecular formula C₃H₈O) is treated with acidified potassium dichromate to form a product 'B' (molecular formula C₃H₆O). 'B' forms a shining silver mirror on warming with ammoniacal silver nitrate. 'B', when treated with an aqueous solution of H₂NCONHNH₂ (semicarbazide), HCl and sodium acetate, gives a product 'C'. Identify the structure of 'C':

• (A)CH₃CH₂CH=N–NHCONH₂Correct
• (B)(CH₃)₂C(CH₃)=N–NHCONH₂
• (C)(CH₃)₂C(CH₃)=N–CONHCH₃
• (D)CH₃CH₂CH=N–CONHNH₂