Find the correct statement.
$(1)$ Generally a gene regulates a trait,but sometimes one gene has an effect on multiple traits.
$(2)$ The trait $AB$-blood group of man is regulated by one dominant allele and another recessive allele. Hence it is co-dominant.

• A
  Both the Statements are wrong.
• B
  Statement $(1)$ is correct.
• C
  Statement $(2)$ is correct.
• D
  Both Statements $(1)$ and $(2)$ are correct.