Odd And Even Numbers - 2

Logic Level 2

Given that \(a\), \(b\), \(c\), and \(d\) are 4 positive integers.

\(ab =\) odd
\(ab + cd =\) odd

How many odd numbers are possible at most?

Also See : Odd And Even Numbers - 1 and Odd And Even Numbers - 3

For more of these see my set Self Created Stuff and \({\color{blue}Logical} \space {\color{green}Reasoning}\)