In the 1950s in the USA, most families had just one phone at home, and wireless phones _______ yet.
A. |
haven't invented |
B. |
haven't been invented |
C. |
hadn't invented |
D. |
hadn't been invented |
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In the 1950s in the USA, most families had just one phone at home, and wireless phones _______ yet.
A. |
haven't invented |
B. |
haven't been invented |
C. |
hadn't invented |
D. |
hadn't been invented |