In which of the following is the $rotatory$ $organ$ (wheel organ) found?

Which one of the following features are true for chordates?
$(a)$ Heart is ventral.
$(b)$ Pharyngeal gill slits present.
$(c)$ Central nervous system is ventral,solid and single.
$(d)$ Post-anal tail is present.
$(e)$ Notochord is present.
Choose the most appropriate answer from the options given below:

Which of the following statements is incorrect regarding $Urochordata$?

Usually,chordates have red blood containing red blood corpuscles. The blood is red due to the presence of the following pigment:

To which phylum do the classes Pisces,Amphibia,Aves,Reptilia,and Mammalia belong?

Select the correct statements with reference to chordates.
$A$. Presence of a mid-dorsal,solid and double nerve cord.
$B$. Presence of closed circulatory system.
$C$. Presence of paired pharyngeal gill slits.
$D$. Presence of dorsal heart.
$E$. Triploblastic pseudocoelomate animals.
Choose the correct answer from the options given below: