Bertha Runs a Fashion Boutique

Bertha runs a fashion boutique. She prefers to personally interact with her customers to gauge the styles that would suit their personality. Her customers also prefer talking to her in person to share their preferences in colors, designs, styles, and fabric as they value her suggestions. The opportunity of _____ is highlighted in the given scenario.

A) having lower overhead costs
B) using technology
C) exploiting market niches
D) providing personal customer service