Perimeter = 140 yards means,
side = ´ 140 = 35 yards = 35 ´ 3 = 105 feet.
\ Area = 105 ´ 105 sq. ft. = 11025 sq. ft.
Hence B.
(Note : From the choice of answers, it can be seen that there is no need to actually multiply 105 by 105 since its value should be very close to 100 ´ 100 = 10000 and only 11025 fits the bill.)