SELECT 
  * 
FROM 
  cscart_product_options_exceptions 
WHERE 
  product_id = 240 
ORDER BY 
  exception_id

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.00345856,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_options_exceptions",
          "access_type": "ref",
          "possible_keys": ["product"],
          "key": "product",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "ref": ["const"],
          "loops": 1,
          "rows": 1,
          "cost": 0.00345856,
          "filtered": 100,
          "attached_condition": "cscart_product_options_exceptions.product_id <=> 240"
        }
      }
    ]
  }
}