____ computer, which was invented in the
题型：选择题
问题：
| ____ computer, which was invented in the 1950s, is widely considered as ____ useful tool in modem society. |
A. The; an B. A; the C. /; an D. The; a |
| ____ computer, which was invented in the 1950s, is widely considered as ____ useful tool in modem society. |
A. The; an B. A; the C. /; an D. The; a |