Answer:
RELATIVELY INELASTIC 
Step-by-step explanation:
MONOPOLISTICALLY COMPETITIVE is a market structure with unrestricted firms entry , many buyers & sellers , selling related but differentiated products, with huge selling costs , imperfect knowledge because of sellers claiming superiority of their product over their competitors . 
Eg : Cosmetics Industry 
Elasticity is the responsiveness of demand to its affecting factors (primarily price) .Goods having close substitutes have more elastic demand & goods having no close substitutes have less elastic demand. Such because former ones are easily replaced by cheaper alternatives / replace expensive alternatives but the latter ones cant. 
In this market case : If products are slightly differentiated (more similar) , implies that they have close substitutes & hence elastic demand . If products are strongly differentiated (less similar) , implies that they have no close substitutes & hence relatively Inelastic demand .