What is the number of right half plane poles in closed-loop transfer function: \(\frac{{{\rm{C}}\left( {\rm{s}} \right)}}{{{\rm{R}}\left( {\rm{s}} \right)}} = \frac{50}{{{{{5s^5}+{35s^4+30s^3+210s^2+40s+280}}}}}\)

• A. 3
• B. 2
• C. 0
• D. 1