The Overall Number of Multiple Births Has Increased Over Recent

Multiple Choice

The overall number of multiple births has increased over recent years largely as a result of

A) improved male fertility and use of more varied coital positions.
B) improved prenatal care among ethnic groups who are more prone to multiple births.
C) intercourse at younger ages and a tendency for women to have more sex partners.
D) more older women becoming pregnant and increased use of fertility drugs.