Which of the Following Best Describes Cuprate Reagents

Which of the following best describes cuprate reagents?

A) They are less nucleophilic than Grignard reagents and promote 1,4-addition of á,â-unsaturated carbonyls.
B) They are more nucleophilic than Grignard reagents and promote 1,4-addition of á,â-unsaturated carbonyls.
C) They are less nucleophilic than Grignard reagents and promote 1,2-addition of á,â-unsaturated carbonyls.
D) They are more nucleophilic than Grignard reagents and promote 1,2-addition of á,â-unsaturated carbonyls.