Phenolphthalein is not a suitable indicator for the titration between which of the following?

The pink color of phenolphthalein in an alkaline medium is due to:

Given below are two statements.
Statement $I:$ In the titration between a strong acid and a weak base,methyl orange is a suitable indicator.
Statement $II:$ For the titration of acetic acid with $NaOH$,phenolphthalein is not a suitable indicator.
In the light of the above statements,choose the most appropriate answer from the options given below:

For an acid-base indicator,the dissociation constant $K_a = 1.0 \times 10^{-5}$. The indicator is red in acidic form and blue in basic form. What is the $pH$ range required for the color change from $80\%$ red to $80\%$ blue?

The best indicator for the detection of the end point in the titration of a weak acid and a strong base is:

Methyl orange gives red colour in