7.13 The average monsoon rainfall for all years from 1871 to 2004 is about 850 millimeters. What effect does El Nio appear to have on monsoon rains?

(a) Strong El Nio years tend to have higher monsoon rainfalls than in other years.

(b) Strong El Nio years tend to have the same monsoon rainfalls as in other years.

(c) Strong El Nio years tend to have lower monsoon rainfalls than in other years.

(d) None of the above.