Indicate Which Chemical Factor Is Responsible for the Effect Described $\mathrm { P } _ { \mathrm { O } _ { 2 } }$

Short Answer

Indicate which chemical factor is responsible for the effect described.
a.arterial $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ between 60 to 100 mm Hg
b.arterial $\mathrm { P } _ { \mathrm { O } _ { 2 } }$ less than 60 mm Hg
c.arterial $\mathrm { P } _ { \mathrm { CO } _ { 2 } }$ increased above normal
d.brain ECF H+ increased above normal
e.arterial H+ increased above normal
-Directly depresses the central chemoreceptors