Mercury has a snyodic period of about 6 months. Why don't we see a transit with this frequency?

Question

a) the sun shines too brightly to see it

b) the orbit of mercury is inclined to the ecliptic by 7 degrees

c) transits never occur near the line of nodes

d) mercury is too small

as you can tell...it's a homework question. I've narrowed it down to either A or B. I don't think C is true, and I don't think D is relevant...but I'm not entirely certain. Could someone point me in the right direction?

Answer 1

B.

A is false -- you *can* see Mercury when it transits.

B is the same reason we don't have a solar eclipse every 29.? days (moon's synodic period), or a lunar eclipse every 14.5? days later.

.

Answer 2

If A or D were true, you'd never see a transit.

Answer 3

b. Moist times they are just conjunctions with Merdury north or south of the sun.  Same thing wih solar eclipses.