Consider the following ratings matrix.

Which item would the user$-$based collaborative filtering algorithm recommend

to user $3(u_3)?$ Which item would the same algorithm recommend to user $7$

$(u_7)?$

$(1)i_3$ to $u_3$ and $i_3$ to $u_7$

$(2)i_5$ to $u_3$ and $i_3$ to $u_7$

$(3)i_3$ to $u_3$ and $i_6$ to $u_7$

$3$

$(4)i_5$ to $u_3$ and $i_6$ to $u_7$