Answer:
Option: C is correct.
( C. The dollar has weakened ).
Step-by-step explanation:
It is given that:
The foreign exchange rate between the U.S. dollar and British pound changed from 1:1 to 1:0.7.
i.e. earlier the U.S. dollar and British Pound were at the same rate.
Now the ratio has changed to 1:0.7
This means that the Dollar has weakened in comparison to the British Pound.
Hence, option: C is correct.
( C. The dollar has weakened )