From Q.188, total for 4 months (Weeks 1–16) = Month1 + Month2 + Month3 + Month4 = Rs.1440 + Rs.2040 + Rs.1920 + Rs.1920 = Rs.7320.
Thus, the total earning is Rs.7320.
Checking incorrect options:
(B) Rs.7800 — higher than actual total, would require extra income somewhere.
(C) Rs.8400 — even higher, unrealistic.
(D) Rs.9600 — not possible from given data.
\(\boxed{\text{Correct Answer: (A) Rs.7320}}\)