According to the guide, social animals should be housed in pairs or groups whenever possible. which of the following is not a good justification for housing animals individually?

Convenience of the research and husbandry staff

Explanation:

It is proper to house social animals nicely because the housing and management of their homes is important to the quality of research data to be gotten when the animals are used for teaching or testing programs.

Animals are properly kept and managed in order to obtain the right species-behaviors required and reduce stress-related behaviors.  

Keeping of animals  should not be for the convenience of the research staff. but for scientific and behavioral reasons also with an eye on associated health problems

b) to encourage free trade

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.