Question

d
are
the extremely thin blood
Vessels which connect arteries to veins​

Answer 1

$\textsf{\textbf{Capillaries} are the extremely thin blood vessels which connect arteries to veins.}$

Answer 2

Answer:

Capillaries

Capillaries. Capillaries are tiny, extremely thin-walled vessels that act as a bridge between arteries (which carry blood away from the heart) and veins (which carry blood back to the heart).  

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