The one-celled eukaryotic organisms above are often found in freshwater ponds. what is one
characteristic they all have in common?
a nucleus
b cilia
c flagellum
d pseudopodia

The correct option is A. Nucleus

Explanation:

The diagram in the question shows a paramecium, euglena and amoeba.

Paramecium can be describe as a fresh water animal which has a body covered with cilia. Flagellum and Pseudopodia lack in paramecium

Amoeba can be described as single celled organisms which have Pseudopodia for movement and shape changing.

Euglena is a single- celled organism capable of living is salt water as well as fresh water. It contains flagellum for movement but lacks cilia and Pseudopodia.

The structure common in all these organisms is the nucleus. Nucleus is present in every eukaryotic organism.

b is the correct answer

transformative rocks are the stones that emerge from the transformation of existing rock composes in a procedure called changeability, implies changing of structures. transformative rocks are shaped from alternate shakes that are changing a result of warmth or weight connected. one of this model is the earth developments that making rocks profoundly cover or crushed which will make the stones warmed and put under awesome weight. they are not softening but rather the minerals they are containing are changed synthetically that will shape transformative rocks. now and again different rocks are shaped when the others are near some liquid magma and getting warmed.