Another structure that most cells have in common is a in the center of the cell, which contains the blueprints for the cell's growth and reproduction.

NUCLEUS

Explanation:

Firstly, the BLUEPRINT of life in living cells is the DNA, which stores the information that encodes the synthesis of products (proteins) that are needed by the cell for growth and reproduction. This DNA is located in a structure in eukaryotic cells called NUCLEUS.

The NUCLEUS is the organelle present in the center of eukaryotic cells, which which contains DNA, which is regarded as the blueprints for the cell's growth and reproduction. Note that, the most cells being referred to in this question are EUKARYOTIC CELLS as prokaryotic cells do not contain a NUCLEUS.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.