E-Trade uses a website to target specific investors who want a low-cost and convenient way to buy stocks online. This is an example of focusing on a specific market. What type of marketing strategy is E-Trade employing?
A) Niche Marketing
B) Mass Marketing
C) Relationship Marketing
D) Viral Marketing

Choose the correct option:
a) A only
b) B and C
c) A and D
d) C only