Fibrous and globular proteins are found in the tertiary structure of proteins. The tertiary structure is stabilised by hydrogen bonds, disulphide linkage and van der Waals' forces. In fibrous proteins, polypeptide chains are held together by hydrogen bonds and disulphide bonds. In the globular proteins, the amino acid chain can twist in a way that polar group lie at the protein's surface due to which it is soluble in water. Globular proteins are spherical in shape. So, the correct match is a-i, a-iv, b-ii, b-iii.