The correct answer would be D. Mollusca.
The question is basically describing a snail.
Arthropoda have segmented bodies.
Echinodermata(starfishes, sand dollars etc.) are radially symmetrical.
Also none of them have shells except phylum Mollusca :)
First question is D poor farming practices
A ph of 7 is considered to be neutral
The cell cycle is the replication and reproduction of cells, whether in eukaryotes or prokaryotes. It is important to organisms in different ways, but overall it allows them to survive. For prokaryotes, the cell cycle, called Binary Fission, allows for them to live on by dividing into two new daughter cells