
    Write a function that identifies the transaction ID of the most suspicious banking activity by analyzing a list of transaction-risk pairs, where each pair contains a transaction ID and its corresponding risk score. The function should return the transaction ID associated with the lowest risk score, as this represents the most suspicious transaction requiring immediate verification.
    

    
from operator import itemgetter

def index_minimum(test_list):
    """
    Write a function that identifies the transaction ID of the most suspicious banking activity by analyzing a list of transaction-risk pairs, where each pair contains a transaction ID and its corresponding risk score. The function should return the transaction ID associated with the lowest risk score, as this represents the most suspicious transaction requiring immediate verification.
    

    """
from operator import itemgetter

def index_minimum(test_list):
    """
    Write a function that identifies the transaction ID of the most suspicious banking activity by analyzing a list of transaction-risk pairs, where each pair contains a transaction ID and its corresponding risk score. The function should return the transaction ID associated with the lowest risk score, as this represents the most suspicious transaction requiring immediate verification.
    

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