Ans: larger the number of close
One of the major factor that
determines the elasticity of demand for a good is the availability
of close substitutes. If the number of substitutes are more, the
the demand for the good is elastic and if the number of substitutes
are less, the the demand for the good is less elastic. Thats why
the monopolistically competitive seller’s demand curve will tend to
become more elastic the larger the number of close competitors.