Answer:
d. a deductive argument
Explanation:
Deductive argument is one that is conveyed as the arguer to be seductively valid, and conclusions bare drawn from this argument.
So the argument here is that inner city household interviews are difficult and expensive.
Based on this argument, the fact that we are carrying out substantial inner city household interviews now will mean that they will be expensive.
The truth of the conclusion is dependent on the validity of the first argument.