Which of the following statements are correct?
$(a)$ Proteins are heteropolymers of amino acids.
$(b)$ The sugar found in nucleic acids is of the $\beta$-type.
$(c)$ Nucleic acids exhibit acidic properties.
$(d)$ $5$-methyl uracil is attached to the first carbon atom of the ribose sugar.
$(e)$ Collagen is the most abundant protein found in the plant kingdom.

• A
  $a, b, e$
• B
  $a, b, d$
• C
  $b, c, d, e$
• D
  $a, b, c$