Is anybody familiar with the 75-5-10 rule related to securities...I think my textbook is wrong, do you agree?

The question reads..."ABC is a diversified, open-end investment company with assets of $20 million, of which $5 million is invested in real estate that it wishes to retain. The rest is invested in securities. ABC wishes to invest in Kramer Manufactures, Inc,. a company whose outstanding stock is valued at $4 million. If ABC wishes to retain its diversified status, what is the most it may invest in Kramer Manufactures, Inc.?"
A. $2 million
B. $1 million
C. $750,000
D. $400,000
The book says the answer is D saying "ABC must comply with the 75-5-10 rule. It wishes to retain its real estate investments, which comprise 25% of its portfolio, or $5 million. Of the remaining $15 million, Kramer Manufactres, may not comprise more than 5% of ABC's assets, and ABC may not own more than 10% of Kramer. The latter figure-$400,000-is the smaller figure, so that is what ABC must limit its investment to." I disagree, don't you...anybody out ther have their series 6 investment exam license?

I say the answer is D. They cant own more than 10 percent of a company's voiting stock, if they want to remain diversified. All the other answers would break that rule.

I agree. $400,000 would be the most ABC could own of Kramer