Which of the following are protein fibers?

The following tetrapeptide can be represented as:
($F, L, D, Y, I, Q, P$ are one-letter codes for amino acids)

The helical structure of proteins is stabilized by

Protein can be most easily removed from which of the following?

Consider the following statements:
Statement-$I$: Lysine and arginine are essential and basic amino acids.
Statement-$II$: Leucine and phenylalanine are non-essential and neutral amino acids.

Which of the following is $NOT$ a globular protein?