Concept:
In the Patanjali Yoga Sutra, Ishwara is described as:
\[
\textit{Purusha-vishesha}
\]
meaning a special Purusha untouched by afflictions, actions, and karmic impressions.
Patanjali also states:
\[
\textit{Tasya vācakaḥ praṇavaḥ}
\]
which means:
\[
\text{Praṇava (Om) is the expression or symbol of Ishwara.}
\]
Thus, Ishwara is identified as the special Purusha whose Vāchaka is Praṇava.
Step 1: Analyze Assertion A.
Assertion A states:
\[
\text{Purushvishesh is called Ishwar which is the Vāchya of Pranava.}
\]
This statement is true because:
• Ishwara is described as a special Purusha.
• Praṇava (Om) is the Vāchaka (expression) of Ishwara.
Hence, Assertion A is correct.
Step 2: Analyze Reason R.
Reason R states:
\[
\text{Ishwar is not the Guru of ancestors because he is not bound with time.}
\]
This statement is false because the Yoga Sutra actually states:
\[
\textit{Sa pūrveṣām api guruḥ kālenānavacchedāt}
\]
Meaning:
\[
\text{``Ishwara is the Guru even of the ancient teachers because he is not limited by time.''}
\]
Thus, Ishwara is the Guru of the ancients.
Step 3: Examine the relationship between A and R.
• Assertion A is true.
• Reason R is false because it incorrectly denies Ishwara as Guru of the ancients.
Therefore:
\[
\text{A is true but R is false}
\]
Step 4: Identify the correct option.
Since Assertion A is true and Reason R is false, the correct answer is:
\[
\boxed{\text{A is true but R is false}}
\]