In the 1960s, Television Westerns Were Extremely Popular

In the 1960s, television westerns were extremely popular.The shows were adventure shows with settings and costumes that were very unlike what really existed.There was Bonanza, Wagon Train, The Virginian, Laramie, etc.When viewers gradually stopped watching this category of programs, production companies found the networks no longer wanted to televise such shows.The production companies used a _________ strategy and stopped production on all television westerns when the networks stopped showing them.

A) diversification
B) aggregation
C) segmentation
D) deletion
E) harvesting