Hi, I am working on a Lightning web component page.I have created a custom lightning page using Lightning web components, having a custom picklist in it, and I am trying to autopopulate the custom picklist on the click of the custom lookup field 'Project'.. Project and Unit is in a Master-detail relationship.

html
<lightning-record-edit-form>
<lightning-card>
<p class="slds-var-p-horizontal_small">
<lightning-record-edit-form object-api-name="Price__c">
<lightning-input-field field-name="Project__c" onchange={projectChange}>
</lightning-input-field>
</lightning-record-edit-form>
<select class="slds-select" >
<option value="Select">Select</option>
<template for:each={options} for:item="option">
<option key={option.label} class="uiInputSelectOption" value={option.value}>{option.value}</option>
</template>
</select>
</p>
</lightning-card>

JS

import { LightningElement , wire, track} from 'lwc';
import getUnit from '@salesforce/apex/PriceFetch.getUnit';
export default class PriceScreen extends LightningElement {
@track options;
projSelected;

projectChange(event) {
this.projSelected = event.detail.value[0];
getUnit({ projId:this.projSelected })
.then(result => { this.options = result; })
.catch(error => { this.options = undefined; }); } }

APEX CLASS

public with sharing class PriceFetch {
@AuraEnabled(cacheable = true)
public static List<Unit__c> getUnit(Id projId) {
return [SELECT Id, Name FROM Unit__c where Project__c = :projId ]; } }

Is there any mistake in my code?