Option B: “bee” refers to an insect and makes a meaningful sentence in this case. Then the sentence would mean that, “A bee is present between the plants.” Hence, this is the correct option.
Options A and D: “be” and “been” are different tenses of the verb “be”, which refers to the quality of existing. This is meaningless in the given case. Hence, this option is incorrect.
Option C: “blue” is a color and thus an attribute. Singularly it will not make any sense, for example, “A blue” does not mean anything. It makes sense when used as an attribute of something, for example, “A blue shirt”. Since, in the sentence it is not attributing to anything it is meaningless in the given case. Hence, this option is incorrect.