
    In a personalized learning system, given a collection of paired data where each pair contains a learning style and its associated student difficulty score, identify the learning style that corresponds to the lowest difficulty score to optimize teaching methods for struggling students.
    

    
from operator import itemgetter

def index_minimum(test_list):
    """
    In a personalized learning system, given a collection of paired data where each pair contains a learning style and its associated student difficulty score, identify the learning style that corresponds to the lowest difficulty score to optimize teaching methods for struggling students.
    

    """
from operator import itemgetter

def index_minimum(test_list):
    """
    In a personalized learning system, given a collection of paired data where each pair contains a learning style and its associated student difficulty score, identify the learning style that corresponds to the lowest difficulty score to optimize teaching methods for struggling students.
    

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