Guys help! A class was studying human body systems. The students learned about a system that moved oxygen to the cells and contained structures that help the body fight infections.
The class was studying the —
A. endocrine system
B. circulatory system
C. digestive system
D. muscular system

B.circulatory system

Explanation:

it would the circulatory because digestive is stomach, endocrine is hormones, and muscular is well your muscles

D muscular system

Explanation:

because the muscular system can fight off anything if your strong

many phylogenetic trees have a single lineage at the base representing a common ancestor. a lineage that evolved early from the root and remains unbranched is called basal taxon. when two lineages stem from the same branch point, they are called sister taxa.

can i get the brainliest pls

explanation:

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.