Modify object before client receiving it on LiveQuery

Question

I am trying to hide some fields in my cloud code for a class with blocking value to a default number in afterFind trigger.

Parse.Cloud.afterFind("Question", async (req) => {
  let objs = req.objects;
  if (req.master) return req.objects;
  objs.forEach(obj => {
    obj.set("answer", -100);
  });
  return objs;
});

It it working fine but when I subscribe to this Class with LiveQuery on update event I can see all fields in my console.

sub.on("update", async (obj) => {
      console.log(obj.toJSON());
      //this.getQuestion(this.cat_id);
    });

Is there any way to modify/block fields in LiveQuery events ?

EDIT:

I am trying to implement protectedFields but it gives same response

var api = new ParseServer({
  databaseURI: databaseUri || 'mongodb://localhost:27017/dev',
  cloud: process.env.CLOUD_CODE_MAIN || __dirname + '/cloud/main.js',
  appId: process.env.APP_ID || 'id',
  masterKey: process.env.MASTER_KEY || 'master', //Add your master key here. Keep it secret!
  serverURL: process.env.SERVER_URL || 'http://localhost:1337/parse',  // Don't forget to change to https if needed
  liveQuery: {
    classNames: ["Message", "Marker", "Question"] // List of classes to support for query subscriptions
  },
  protectedFields: {
   Question: {
    "*": ["answer", "active"]
   }

} });

LiveQuery :

async subToQuestions(category) {
  let questionQuery = new Parse.Query(Question);
  questionQuery.equalTo("category", category);
  try {
    return await questionQuery.subscribe();
  }
  catch (e) {
    throw e;
  }
}

category is a pointer

async subToQuestion(cat) {
    let sub = await this.ParseService.subToQuestions(cat);
    sub.on('create', async (obj) => {
      console.log(obj.toJSON());
    });
    sub.on("update", async (obj) => {
      console.log(obj.toJSON());
    });
  }

When I log the result of LiveQuery it prompts protected fields too.

And beforeFind for Question class

Parse.Cloud.beforeFind("Question", async (req) => {
  let query = req.query;
  query.limit(1);
  query.equalTo("active", true);
  let now = new Date();
  query.greaterThan("close_date", now);
  query.include(["close_date", "text"]);
});

Query example