The correct option is B.
Idea models refers to those models that are used to show the relationships that exist between abstract concepts. The model is used basically to bring about desired changes and it normally used in business and other sectors to visualize how an idea might work out. Idea models are usually presented in form of graphs and equations, the variables in these graphs and equations show the relationships between the variables that are been considered.
The phrase "was really looking forward to it" creates the excited mood.
Hope this helps!
As trees takes in carbon dioxide and gives out oxygen, it is almost similar to how our lungs work in our respiratory system. As you know, lungs remove carbon dioxide from our body and transports oxygen in order for us to survive. So the tropical rainforests gives out oxygen for our survival needs, which is somewhat similar.
I hope you understand lawl
Eco- friendly means earth friendly or not harmful to environment