causes lenders to lose *\no inflation\no idk\no infrastructure\no interest

Brief Explanations:

Inflation erodes the real - value of money repaid by borrowers to lenders. When there is inflation, the purchasing power of the money that lenders get back is less than when they lent it out. Infrastructure and "IDK" (I don't know) are not relevant in this context. Interest is what lenders earn, not what causes them to lose.

Answer:

A. inflation