Correct option is c) less than 4 mole of B
Equivalent weight of compound A = \(\frac{M_A}4\)
Equivalent weight of compound B = \(\frac{M_B}5\)
∴ Number of equivalents in 4 mol of A = 4 x 4 = 16 equivalent
∴ To complete reaction of A WIth Compound B,
Compound B required = 16 equivalent
= or 3.2 mole of Compound B
Therefore, we required, less than 4 mol of compound B.