
    Write a function that identifies the transaction ID from a list of credit card transactions with the lowest fraud risk score, where each transaction is represented as a tuple containing the transaction ID and its fraud risk score. The function should return the transaction ID that requires the most urgent investigation based on having the most suspicious (lowest) risk score.
    

    
from operator import itemgetter

def index_minimum(test_list):
    """
    Write a function that identifies the transaction ID from a list of credit card transactions with the lowest fraud risk score, where each transaction is represented as a tuple containing the transaction ID and its fraud risk score. The function should return the transaction ID that requires the most urgent investigation based on having the most suspicious (lowest) risk score.
    

    """
from operator import itemgetter

def index_minimum(test_list):
    """
    Write a function that identifies the transaction ID from a list of credit card transactions with the lowest fraud risk score, where each transaction is represented as a tuple containing the transaction ID and its fraud risk score. The function should return the transaction ID that requires the most urgent investigation based on having the most suspicious (lowest) risk score.
    

    """
    res = min(test_list, key=itemgetter(1))[0]
    return res