Answer & Explanation
D) I, II and III together
From III, we have : Rajan's basic salary = Rs 1550.
From I, we have : Vasu's basic salary = Rs (1550 + 100) = Rs 1650.
From II. we have : Rajan's other allowances = RS 2000
and Vasu's other allowances = Rs 2050.
Vasu's monthly salary is (1650 + 2050) = Rs 3700.
Thus, all the three statements are required.