Step 1: Understanding the Concept:
The question asks to identify the modern linguist who praised Pāṇini's grammatical treatise, the Aṣṭādhyāyī, with the given high commendation.
Step 2: Detailed Explanation:
This famous tribute to Pāṇini was made by the highly influential American linguist Leonard Bloomfield. In his seminal 1933 book, "Language," which became a foundational text for structural linguistics in America, Bloomfield described Pāṇini's Aṣṭādhyāyī as "one of the greatest monuments of human intelligence."
He saw Pāṇini's work as a model of formal, descriptive analysis, unparalleled in its thoroughness and internal consistency until the 19th century. Bloomfield's acknowledgment was pivotal in establishing Pāṇini's reputation in the world of modern linguistics as a forerunner of structuralist thought.
Ferdinand de Saussure: The Swiss "father of modern linguistics," was also influenced by Pāṇinian grammar, but this specific quote is not his.
Patrick Olivelle: A contemporary scholar and translator of Sanskrit texts.
Nāgeśa Bhaṭṭa: A great Indian grammarian of the 18th century who worked within the Pāṇinian tradition.
Step 3: Final Answer:
The acknowledgment was made by Leonard Bloomfield. Therefore, option (3) is correct.