Grammar question

[gameplayer1234]

Tornadoes form when large air masses of different temperatures (collide, which results from either a change in) the direction or the speed of the wind.A)collide, which results from either a change inB)collide, resulting either from a change inC)collide as the result of a change in eitherD)have collided either as the result of a change inE)colliding results from either a change to.
Ans: c
Why not a or b ?

Running outdoors burns about five percent morecalories than if you are running on a treadmill,in part this is because there is greater windresistance outdoors.(A) if you are running on a treadmill, in part thisis because there is(B) if you run on a treadmill, in part because of the© when running on a treadmill, in part becauseof the(D) running on a treadmill, which is in part becauseof the(E) running on a treadmill, in part because there is.
Ans: E
Why note D ?

[marvin100]

Tornadoes form when large air masses of different temperatures (collide, which results from either a change in) the direction or the speed of the wind.
A)collide, which results from either a change in
B)collide, resulting either from a change in
C)collide as the result of a change in either
D)have collided either as the result of a change in
E)colliding results from either a change to.
Ans: c
Why not a or b ?

(A) ambiguous “which.” “Which” can’t be applied to a whole phrase without the addition of a noun, like “an action which results…” or “a phenomenon which results.”
(B) isn’t parallel. The parallel structure is “either A or B”, and in this case that would be “from a change” and “the speed,” and a prepositional phrase isn’t parallel with a noun phrase. The “from” should precede the “either” to make it apply to both A and B.

Running outdoors burns about five percent more calories than if you are running on a treadmill,in part this is because there is greater wind resistance outdoors.
(A) if you are running on a treadmill, in part this is because there is
(B) if you run on a treadmill, in part because of the
(C) when running on a treadmill, in part because of the
(D) running on a treadmill, which is in part because of the
(E) running on a treadmill, in part because there is.
Ans: E
Why note D ?

(D) ambiguous pronoun again–same rule as (A) above. This is a frequently tested principle, so you should learn it and learn to spot it ASAP.

Best of luck, @gameplayer1234

[gameplayer1234]

thank you @marvin100 i cant deny that you have perfect explanations
can you please critisize my essay ?

[marvin100]

@gameplayer1234 - I’m sorry, but I’m usually too busy for essays. Grammar Qs are quick & easy

[gameplayer1234]

Yeah no problem. You helped more than enough @marvin100