Sentence Correction

Lacking information about energy use, people tend
to overestimate the amount of energy used by
equipment. such as lights, that are visible and must
be turned on and off and underestimate that used
by unobtrusive equipment, such as water heaters.
A) equipment, such as lights, that are visible and
must be turned on and off and underestimate
that
B)equipment, such as lights, that are visible and
must be turned on and off and underestimate it
when
C )equipment, such as lights, that is visible and
must be turned on and off and underestimate it
when
D)visible equipment, such as lights, that must be
turned on and off and underestimate that
E) visible equipment, such as lights, that must be
turned on and off and underestimate it when


Can someone please help me in eliminating choice between D and E specially between that and it?
OA D

thanks.

try to read like this:

people tend to

1st part--overestimate the amount of energy used by visible equipment
AND
2nd part--underestimate the amount of energy used by unobstructive equipmentD referes to 'THAT'---the amount of energy.D goes perfectly parallel now if we try E.

It will look like this:though 'it' should not refer the amount of energy
E.
people tend to underestimate the amount of energy when used by unobstructive equipment.which is wrong

'that' in D is a restrictive pronoun. 'energy' means all energy used by all equipments. 'that' restricts the reference to 'he energy used
by unobtrusive equipment, such as water heaters', by modifying 'energy'

'it' in E, sounds somewhat (not completely) like the same energy that was used by lights when re-used by unobtrusive equipments.

I know, this may sound a bit confusing as 'it' may or may not mean the same energy. But 'that' certainly means energy used by different equipments. Hence, go for the sentence with clearer meaning.