It is b. If I am wrong I am sorry
The correct answer to this question is this one: "sporozoans lack locomotor organs"
The feature that differentiates sporozoans from the other phyla of protozoans is that sporozoans lack locomotor organs. Sporozoans are a strictly parasitic protozoan that are usually immobile.
The correct answer is the last option.
The first option (unable to cause climate change) is incorrect because these gases do effect the atmospheric temperatures by increasing them.
The second option is incorrect because while these gases do cause more water vapor to condense, they result in acid rain (not wetter climates).