Have ya seen these kinds of CATs and DOGs

I happen to learn some interesting idoms when surfing the web site. Here I really love to share it with ya :)
　　
Well, everybody knows what “It rains cats and dogs“ means, but do you exactly know what “cat“ and “dog“ mean?
　　
Don’t answer me without hesitate, do the following test and u will understand why I ask u so “stupid“ question :))
　　
　　1.You stand no chance of being able to do this. You don’t have a ______ chance in hell.
　　A. cat’s B. dog’s (Key: A)
　　
　　2.The negotiations were really difficult. Both sides played ______ and mouse with each other.
　　A. cat B. dog (Key: A)
　　
　　3.There is a shortage of water here during the ______ days of Summer.
　　A.cat B. dog (Key: B)
　　
　　4.I’ve never seen him so happy. He’s like a ______ with two tails.
　　A.cat B. dog (Key: B)
　　
　　5 You’ll get promoted one of these days. Every ______ has its day.
　　A.cat B. dog (Key: B)
　　
　　6.Where on earth have you been? Your hair is a mess and your clothes are dirty. You look like something the ______ has brought in.
　　A.cat B. dog (Key: A)
　　
　　7.It’s a very tough environment on Wall Street. It’s a ______ world.
　　A. cat eat cat B. dog eat dog
　　C.cat eat dog D. dog eat cat (Key: B)
　　
　　8.I don’t know why you have applied for the job. You don’t have a ______ chance of getting it.
　　A. cat’s B. dog’s (Key: B)
　　
　　9.Why won’t you say anything? Has the ______ got your tongue?
　　A.cat B. dog (Key: A)
　　
　　10.I lost one of our major clients and now I’m in the ______house with my boss.
　　A.cat B. dog (Key: B)
　　
　　11.Nobody did any work whilst the boss was ill. As they say, when the ______ away the mice will play.
　　A. cat’s B. dog’s (Key: A)
　　
　　12.I’ve agreed with the bank that they will call off the ______ and give us a chance to find some more capital elsewhere.
　　A. cats B. dogs (Key: B)
　　
　　13.It was supposed to be a secret. Why did you have to let the ______ out of the bag?
　　A. cat B. dog (Key: A)
　　
　　14.This country is doing really badly. It’s going to the ______ .
　　A. cats B. dogs (Key: B)
　　
　　15.Ever since he got that big order, he’s been walking around like the ______ that got the cream.
　　A. cat B. dog (Key: A)
　　
　　16.This press release will get everybody talking. It will certainly put the ______ among the pigeons.
　　A. cats B. dogs (Key: A)
　　
　　17.She just won’t sit still. She moving around like a ______ on a hot tin roof.
　　A. cat B. dog (Key: A)
　　
　　18.They made me take the blame for their mistakes. They really threw me to the ______ .
　　A. cats B. dogs (Key: B)
　　
　　19.I cannot do any more exercises. I’m ______ .
　　A. cat-tired B. dog-tired (Key: B)
　　
　　Have ya got right all the questions? TELL ME~~~~ :))