See this conversation which is written by a non-native English teacher
A: Let's go to the zoo
B: Which animals do you want to see in the zoo?
A: I wanna see the lions.
First of all, "A" can say "the zoo" at the beginning of the conversation because maybe both "A" & "B" know that specific zoo. Maybe "A" & "B" live in the same city & there is only one zoo in that city.
So, I would say "A: Let's go to the zoo" is a proper expression
However, see the next expression "B: Which animals do you want to see in the zoo?"
Cambridge Grammar says:
We use both "which" and "what" to ask questions. We use "which" when there is a restricted range of answers. We use what more commonly when the range of answers is not restricted:
Which is the capital of Liberia? Monrovia or Greenville?
What’s the capital of Liberia?
There would be hundreds of animals in the zoo & I don't think "A" or "B" can remember specifically all these animals.
So, I would say "Which animals do you want to see in the zoo?" should be changed to "What animals do you want to see in the zoo?"
Finally, I would say "A: I wanna see the lions." is not a proper expression since "B" may not be able to figure out what the specific lions A is talking about. "B" may have responded "B: What lions are you taking about?".
I would guess that "A" wants to see all lions generally.
However, this site says
You can use the with the singular form of a countable noun when you want to make a general statement about all things of a particular type.
The computer allows us to deal with a lot of data very quickly.
My father's favourite flower is the rose.
But I am not sure "A" can say "A: I want to see the lion." (the lion: all things of a particular type.)
Therefore, I would say "A: I want to see the lions." should be changed to "A: I want see lions."
Am I right?