Codecademy Challenge Project: Mysterious Organism

Link to the Challenge project on codecademy

I am working on step four at the moment and am stuck, I am not sure if my code works as when I try to console.log or return it, it only says the callback function, I am probably missing some tiny thing or just being plain stupid, but any help would be greatly appreciated

Here are the results I’m getting:

{ specimenNum: 8,
dna: [Function: mockUpStrand],
mutate: [Function: mutate] }
[Function: mockUpStrand]
{ [Function: mockUpStrand] ‘10’: [Function: returnRandBase] }

I have no idea why it is saying 10, it should be saying one of the letters ‘A’ ‘T’ ‘C’ or ‘G’

Here is my code:

// Returns a random DNA base const returnRandBase = () => { const dnaBases = ['A', 'T', 'C', 'G'] return dnaBases[Math.floor(Math.random() * 4)] } // Returns a random single strand of DNA containing 15 bases const mockUpStrand = () => { const newStrand = [] for (let i = 0; i < 15; i++) { newStrand.push(returnRandBase()) } return newStrand } // factory function - makes objects const pAequorFactory = (num, basesArr) => { object = { specimenNum: num, dna: basesArr, mutate() { randomNum = Math.floor(Math.random() * 15) digitCheck = object.dna[randomNum] object.dna[randomNum] = returnRandBase console.log(returnRandBase) if (object.dna[randomNum] === digitCheck) { object.mutate() } else { return object.dna } } } return object } console.log(pAequorFactory(8, mockUpStrand)) console.log(object.dna) object.mutate() console.log(object.dna)

On this line:
console.log(pAequorFactory(8, mockUpStrand)),
you want what the mockUpStrand function returns to be one of the arguments, so the that should be a function call:
should be

on the line:
object.dna[randomNum] = returnRandBase
You want the result of the function call, not the function itself, to be inseted into the .dna array.
should be