Keywords, Sub Track default text should be changed because user can't get any idea when using a screen reader

Steps to Reproduce

1. Go to https://www.topcoder.com/challenges
2. Open the Screen Reader
3. Click Filters
4. Click Keywords/Sub Track drop downs

Expected Result Keywords: Keywords and Sub Track: Sub Track

Actual Result Keywords: Select... and Sub Track: Select...

Device: Desktop/Labtop Operating System: Windows Browser: Chrome

WCAG Category: 1. Perceivable WCAG Level: A WCAG Success Criterion: 1.3.1 Info and Relationships Screen Reader Used: JAWS Accessibility Audit Tool used: N/A

Attachment https://topcodermsft-my.sharepoint.com/personal/pd-topcoder_topcodermsft_onmicrosoft_com/Documents/Forms/All.aspx?cid=58da9b68%2Df2a3%2D45d2%2Dbbae%2D15abdfd0865b&FolderCTID=0x0120005C598A51049FC14CBA882E1AEE168F51&sortField=Modified&isAscending=true&id=%2Fpersonal%2Fpd%2Dtopcoder%5Ftopcodermsft%5Fonmicrosoft%5Fcom%2FDocuments%2FMSFT%2DTeams%2DQA%2FJune%202019%2F29%20Jun%2FTest%20Results%2FBug%20Videos%20%26%20Log%20Files%2Fcodejam%2DAccessibility%2F55

Final Submission Guidelines

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