Reading passages

225- Insects are regarded as valuable in biology because ................. .
A) scientists have grown used to working with them
B) they enlighten many dark sides in this field
C) they have many similarities with mankind
D) people consider them to be good-natured
E) of their low cost and simplicity
Mars is the fourth planet in order of distance from the Sun and seventh in order of diminishing size and mass. It orbits the Sun once in 687 Earth days and spins on its axis once every 24 hours and 37 minutes. Owing to the relatively large irregularity of its orbital ellipse, the distance between Mars and the Sun varies from 206.6 million to 249.2 million km. Mars completes a single orbit in roughly the time in which the Earth completes two. At its closest approach, Mars is less than 56 million km from the Earth, but it recedes to almost 400 million km. Most Earth-based observations of Mars are best made when the planet is in the opposite direction in the sky to the Sun, allowing all-night viewing when Mars is closest to the Earth.
226- From the figures in the passage, it can be determined that ............. .
A) a year on the Earth is approximately 322 days shorter than that on Mars
B) the distance between the Sun and Mars is nearly 228 million km
C) there are 11 planets revolving around the Sun, the farthest of which is Mars
D) Mars and the Earth completes and orbit around the Sun in the same period of time
E) there isn't much difference between the closest and furthest points of Mars to the Sun
227- The distance between Mars and the Sun changes due to ................ .
A) the big eccentricity of the former’s oval-shaped appearance
B) the latter’s irregular shape
C) the fact that there are atmospheric conditions in space
D) the fact that the former completes its tour around
the latter much later than the Earth
E) the undetectable rays emerging from the other planets between them