Knowing the distance of the source .......... unless the direction is indicated.

Knowing the distance of the source … unless the direction is indicated.
A. of hive does not help
B. where the hive help
C. where not helping hive
D. from the hive is no help [color=green](Answer Key)

Source: university exam

Hi,
I have some problems with this question:

  1. I can’t understand the meaning of the whole sentence that what it’s talking about. Could you please be kind enough to clarify it to me?

  2. Why can’t A, B and C work?

Thank you.

It’s speaking about something (possibly a food source) and how far away it is from a hive (an insect hive of some sort)

The speaker is saying that for the information to be helpful, he requires both the distance between the hive and the source and the direction of travel from the hive to the source… so he is seeking information along the lines of:
The (food) source is 2 km (away) from the hive in a southerly direction.
It is not enough for his (unstated) purpose to just know that
The (food) source is 2 km (away) from the hive.
He needs to know in what direction the insects have to travel as well as how far they have to travel.