SELECT 
  a.option_id, 
  a.product_id 
FROM 
  cscart_product_options AS a 
WHERE 
  a.product_id IN (3518, 47654, 2920, 3408) 
  AND a.status = 'A'

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "a",
          "access_type": "range",
          "possible_keys": ["c_status"],
          "key": "c_status",
          "key_length": "6",
          "used_key_parts": ["product_id", "status"],
          "rows": 4,
          "filtered": 100,
          "index_condition": "a.product_id in (3518,47654,2920,3408) and a.`status` = 'A'"
        }
      }
    ]
  }
}