Task: Question Answering
Input (English): Problem: in a certain supermarket, a triangular display of cans is arranged in 9 rows, numbered 1 through 9 from top to bottom. each successively numbered row contains 3 more cans than the row immediately above it. if there are fewer than 120 cans in the entire display, how many cans are in the seventh row ?
Options: a. 13, b. 15, c. 17, d. 19, e. 21
Output (English): d