When a Person with a near Point at 28 Cm $6.0 \mathrm {~cm}$

Multiple Choice

When a person with a near point at 28 cm uses a certain magnifying glass, it produces an angular magnification of 7.0 with the image very distant. What is the focal length of the lens of this
Magnifying glass?

A) $6.0 \mathrm {~cm}$
B) $5.0 \mathrm {~cm}$
C) $2.0 \mathrm {~cm}$
D) $3.0 \mathrm {~cm}$
E) $4.0 \mathrm {~cm}$