system: You are an expert security code reviewer. You will be shown a source code file along with a multiple-choice question listing several function or class names from that file. Your task is to identify which one contains the specified CWE vulnerability.

OUTPUT FORMAT: Respond with the single letter of the correct option, wrapped in \boxed{...}. Example: `\boxed{B}`. Output the boxed letter ONLY -- no explanation, no other text.

user: ```python
#!/usr/bin/env python3

import os, re, pyyoutube, jinja2, urllib.request, requests, json
from jinja2 import Template

API_KEY = os.environ["API_KEY"]
EPISODES_PATH = os.environ["EPISODES_PATH"]
IMAGES_REL_PATH = os.environ["IMAGES_REL_PATH"]
IMG_PATH_PREFIX = os.environ["IMG_PATH_PREFIX"]
PLAYLIST_ID = os.environ["PLAYLIST_ID"]
TEMPLATE_FILE = os.environ["TEMPLATE_FILE"]


TITLE_PREFIX = "TGI Kubernetes"
TITLE_SUFFIX = ":"

def getLatestExistingEpisodeNumber():
    filelist = os.listdir(EPISODES_PATH)
    episodes = []
    for filename in filelist:
        try:
            episodes.append(int(re.compile(r"(\d+)").match(filename).group(1)))
        except:
            pass
    return max(episodes)

def getEpisodeNumberFromTitle(title):
  return int(title.split(TITLE_SUFFIX)[0][len(TITLE_PREFIX):])

def getNewEpisodesInPlaylist(playlistId, above):
    api = pyyoutube.Api(api_key=API_KEY)
    list = api.get_playlist_items(playlist_id=playlistId,count=None)
    episodes = []

    YT_API_BASE_URL = "https://www.googleapis.com/youtube/v3/videos"
    YT_API_QS = "?part=snippet%2CliveStreamingDetails&key=" + API_KEY

    for item in list.items:
        videoId = item.snippet.resourceId.videoId
        response = requests.get(YT_API_BASE_URL + YT_API_QS + "&id=" + videoId)
        videoList = json.loads(response.text)
        videoInfo = videoList["items"][0]["snippet"]
        liveInfo = {}

        try:
            liveInfo = videoList["items"][0]["liveStreamingDetails"]
        except:
            liveInfo["scheduledStartTime"] = ""

        episodeNumber = getEpisodeNumberFromTitle(videoInfo["title"])
        video = {
            "videoId": videoId,
            "title": videoInfo["title"],
            "description": videoInfo["description"],
            "imageUrl": videoInfo["thumbnails"]["medium"]["url"],
            "date": liveInfo["scheduledStartTime"],
            "episode": str(episodeNumber).zfill(4),
            #"live": videoInfo["liveBroadcastContent"]
        }
        if (episodeNumber > above-5): # Do the last 5 episodes all the time to make sure we update them
            episodes.append(video)
            print("Saving episode " + video["episode"] + "...")
        else:
            print("Skipping episode " + video["episode"] + " (already have it)...")
    return episodes
        
def writeNewEpisodeFiles(videos):
    templateLoader = jinja2.FileSystemLoader(searchpath="./")
    templateEnv = jinja2.Environment(loader=templateLoader)
    template = templateEnv.get_template(TEMPLATE_FILE)
    for video in videos:
        imageFilename = IMG_PATH_PREFIX + IMAGES_REL_PATH + video["episode"] + ".jpg"
        markdownFilename = EPISODES_PATH + video["episode"] + ".md"
        urllib.request.urlretrieve(video["imageUrl"], imageFilename)
        video["image"] = IMAGES_REL_PATH + video["episode"] + ".jpg"
        outputText = template.render(video=video)
        f = open(markdownFilename, "w")
        f.write(outputText)
        f.close()

latestExistingEpisode = getLatestExistingEpisodeNumber()
videos = getNewEpisodesInPlaylist(PLAYLIST_ID, latestExistingEpisode)
writeNewEpisodeFiles(videos)




```

Which of the following functions or classes contains a `CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')` vulnerability?

  A) getEpisodeNumberFromTitle
  B) getLatestExistingEpisodeNumber
  C) writeNewEpisodeFiles
  D) getNewEpisodesInPlaylist
Answer: C