I think c6h5-ch(ch2) (nh2) used to resolve, beacouse optically active compound used in the resolution.

Introduction:
In organic chemistry, resolving agents are used to separate racemic mixtures into their individual enantiomers. Amines can be used as resolving agents for recemic carboxylic acids through the formation of diastereomeric salts. The amine reacts with the carboxylic acid to form a salt, and the resulting diastereomers can be separated.

Explanation:
To determine which of the given amines can be used as resolving agents, we need to consider the chirality of the amines and their ability to react with carboxylic acids.

A) (-)C6H5-CH(CH3)NH2:
This amine is chiral due to the presence of a stereocenter (the carbon bonded to the nitrogen). It can potentially form diastereomeric salts with carboxylic acids and therefore can be used as a resolving agent.

B) ( )C6H5-CH(CH3)NH2:
The chirality of this amine is not clear from the given information. Without knowing the stereochemistry at the stereocenter, it is difficult to determine if it can be used as a resolving agent. Therefore, we cannot conclude whether this amine can be used or not.

C) CH3NH2:
This amine is not chiral since it does not have a stereocenter. It cannot form diastereomeric salts with carboxylic acids and therefore cannot be used as a resolving agent.

D) CH3CH(CH3)NHCH3:
This amine is chiral due to the presence of a stereocenter (the carbon bonded to the nitrogen). It can potentially form diastereomeric salts with carboxylic acids and therefore can be used as a resolving agent.

Conclusion:
Based on the given information, amines A) (-)C6H5-CH(CH3)NH2 and D) CH3CH(CH3)NHCH3 can be used as resolving agents for recemic carboxylic acids. Amine B) ( )C6H5-CH(CH3)NH2 cannot be determined without further stereochemical information. Amine C) CH3NH2 cannot be used as a resolving agent due to its lack of chirality.