a) Dolomitic Lime
b) Roman Lime
c) Semi-Hydraulic Lime
d) Selentic Lime

Answer: b
Explanation: Semi-Hydraulic Lime contains lesser clay content than Hydraulic Lime. Dolomitic Lime comprises of high magnesium carbonate (35-46%) content. Selentic Lime is cement of grey chalk, with added gypsum. Roman Lime does not exist, instead there is Roman Concrete which is obtained by mixing lime and volcanic ash.