exercise question
 

1.Your prompt action____a seriois accident.
Aattracted B avoided C fought D prevented
Key is D but i chooe B. Why B is not Ok?

2.The job is much easier than I____
A.guessing B.guessed C would have guessed D guess
remember one sentence is "than i expected" so i chooe B. But the key is C. i am puzzled. Why?

Thanks in advance

Re: exercise question
 

Both the B options which you chose are possible.

1. Option B : Here are some authentic examples of avoid collocating with accident:

A lower speed may well reduce the level of injury, but it will not avoid the accident
How to Avoid an Accident on a Motorcycle.
The school knew of the problem with the vandals and should have checked the rugby pitch properly before playing a rugby game to avoid an accident occurring. ...

Option D is also possible of course. Here are some authentic examples of prevent an accident :
Information obtained from an accident investigation is used to help prevent future accidents from happening.
There are a lot of precautionary measures that both employers and employees can take to prevent an accident at work.

2. Option B would be possible in this situation : I started a new job as assistant to a boss who has a reputation for overloading people with work. Before starting, I guessed/imagined that it would be difficult. But now that I've started I realise it isn't difficult at all. It's much easier than I guessed.
Here's an authentic example :
It was much easier than I guessed it would be to switch from my own dedicated host to a shared host. - in other words, when I thought about it afterwards it surprised me how easy it had been.

Option C would be used in this situation : A friend just came to see me and told me he'd not been in touch for 6 months because he'd been away, working as an astronaut on the International Space Station. He told me how easy it was. I didn't know about his job, so I'd never thought about it before. When I tell my husband about it later that evening, I say : The job is much easier than I would have thought (ie if I had thought about it before).

ie : Option B would be used in a situation where my "guess" had really happened previously. Option D in a situation where I hadn't actually thought about it before but know that, hypothetically, if I had thought about it I would have guessed it was difficult. An authentic example :
... moving to WordPress has been much, much easier than I would have guessed.

I don't know what book these come from, but the activities have not been checked adequately for the possibility of alternative answers.