The main difference between terrestrial planets and gas giants is
a) the way they were formed.
b) the shape of their orbits.
c) the level of their density.
d) the plane in which they lie.

Terrestrial planets are:

inner planetssmaller in sizerocky in nature and hence more densehave a few or no moon(s).In our solar system, Earth, Mars (and others) are terrestrial planets

Gas giants are:

outer planetslarger in sizeless dense, have multiple moons.In our solar system, Jupiter and Saturn are gas giants

Well let's uhmmm how many bedrooms you want. if you want a garage. not to mention the price of the house?