Placeholder "IT" and pronoun "it"

[duyng9989]

I have a question about placeholder "it" and pronoun "it".

How can we know "it" in a sentence a placeholder or a pronoun.

For example: it is nice today. (it is place holder to represent for weather)
It is futile to resist

I ask the question because I am confused with one of OG question:

Q57 OG 12:
That educators have not anticipated the impact of microcomputer technology can hardly be said that it is their fault : Alvin Toffler, one of the most prominent students of the future, did not even mention microcomputers in Future Shock, published in 1970


(A) That educators have not anticipated the impact of microcomputer technology can hardly be said that it is their fault to lower the underground water level and to dig trenches
(B)That educators have not anticipated the impact of microcomputer technology can hardly be said to be at fault
(C)It can hardly be said that it is the fault of educators who have not anticipated the impact of microcomputer technology
(D)It can hardly be said that educators are at fault for not anticipating the impact of microcomputer technology
(E)The fact that educators are at fault for not anticipating the impact of microcomputer technology can hardly be said.

I narrowed down to C vs D. Eventually, I picked C becasue I have never heard "sbd is at fault" before.
In this post og-sc-50-t713.html

Stacey said that 'it' is ambiguous. I dont know why because I thought that the second "it" is still similar to the fist "it" - a placeholder.

Could you help me clarify the problem?

PS: I cannot post on the previous post. I dont know why but it said that the forum is locked???

Thank you

[tim]

In MOST cases, "it" is being used as a placeholder if it shows up at the beginning of the sentence as the subject. Otherwise, look for an antecedent.

[duyng9989]

Sorry. I got the answer.

katharine-graham-t2120.html

[tim]

No need to apologize. In fact, you are to be commended for doing some research on your own!