[单选题]
An electron is held up against h3 3k/)y;xms0:xd.ta d5ky; xnsnipx; j,eyethe force of gravity by the attraction e:r;6 4ojc q vv*nyq-iof a fixed proton some distance above it. How far above the electron is the proton?e;v:qi nq*j 4yorv6-c
A. $1.5 \; m$
B. $2.3 \; m$
C. $3.7 \; m$
D. $5.1 \; m$
