Friction can point forward

A 3 kg solid cylinder is pulled horizontally rightward at its top with a 9 N force. It rolls on a stationary horizontal plane. Take I=mr²/2, g=10 m/s² and μ_s=0.20.

What is the signed friction force, with rightward positive?

Organize the givens & assumptions

Mass: 3 kg
Top force: +9 N
I/(mr²)=1/2
μ_s=0.20

Rigid no-slip motion to be checked; no rolling resistance; the pull is horizontal and tangent at the top.

A $+3\ \mathrm N$
B $-3\ \mathrm N$
C $0$
D $+9\ \mathrm N$

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